Cementitious slurries, methods, and assemblies for electrically grounding and corrosion-protecting a metallic structure

ABSTRACT

A method for electrically grounding and corrosion-protecting a metallic structure includes combining a cementitious powder with water to form a cementitious slurry, applying the cementitious slurry to at least a section of the metallic structure, and curing the cementitious slurry to form a water impermeable and electrically conductive cementitious surround on the section. The cementitious powder includes a cement and a particulate carbonaceous material. The cementitious powder is combined with the water in a ratio of less than or equal to about 2.5 US gallons of water per 55 lb of cementitious powder.

CROSS REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/837,284 filed on Apr. 1, 2020, which claims the benefit of UnitedStates Provisional Patent Application No. 62/949,489, filed on Dec. 18,2019, both of which are incorporated herein by reference in theirentirety.

TECHNICAL FIELD

This document relates to metallic structures, such as metallic poles(e.g. utility poles) and/or anchor rods for guy wires. Morespecifically, this document relates to the electrical grounding of suchstructures, the protection of buried portions of such structures fromcorrosion, and the support of such structures.

BACKGROUND

U.S. Pat. No. 10,262,773 (Sirola et al.) discloses a method forprotecting a conductive metal from corrosion, including coating theconductive metal with a water impermeable carbonaceous conductivematerial to protect the conductive metal from corrosion.

SUMMARY

This summary is intended to introduce the reader to the subject matterof the detailed description, and is not intended to define or delimitany invention.

Electrically grounded and corrosion-protected assemblies are disclosed.According to some aspects, an electrically grounded andcorrosion-protected assembly includes a metallic structure. At least aportion of the metallic structure is buried in the earth. A waterimpermeable and electrically conductive cementitious surround is appliedto at least a section of the portion that is buried in the earth. Thesurround is in direct contact with the section and is between thesection and the earth.

In some examples, the surround has a top edge, and the assembly furtherincludes a diverter positioned on the top edge and extending around themetallic structure. The diverter is shaped to direct water away from themetallic structure.

In some examples, the metallic structure is a pole. In some examples,the metallic structure is an anchor rod. In some examples, the metallicstructure is a cladding on a non-metallic structure.

In some examples, the cementitious surround includes a cementitiousmatrix and a particulate carbonaceous material dispersed in thecementitious matrix. The cementitious matrix can include Portlandcement. The particulate carbonaceous material can include calcinedpetroleum coke. The cementitious surround can include between 5 wt % and70 wt % Portland cement, and between 30 wt % and 90 wt % calcinedpetroleum coke. The cementitious surround can include up to 50% slag.

In some examples, the surround has a compressive strength of at least 50psi.

In some examples, the assembly further includes an electricallyconductive and water impermeable jacket encasing the surround. Thejacket can include a polymeric matrix, and a particulate carbonaceousmaterial dispersed in the polymeric matrix.

In some examples, the assembly further includes an electricallyconductive and water impermeable brace embedded in the surround andsupporting the metallic structure. The brace can include a polymericmatrix, and a particulate carbonaceous material dispersed in thepolymeric matrix.

In some examples, the surround holds the metallic structure in agenerally vertical position.

A method for electrically grounding and corrosion-protecting a metallicstructure is also disclosed. According to some aspects, the methodincludes a) applying a cementitious product to at least a section of ametallic structure, wherein the cementitious product includes acementitious matrix and a particulate carbonaceous material dispersed inthe matrix; and b) curing the cementitious product to form a waterimpermeable and electrically conductive cementitious surround on thesection.

In some examples, the method further includes, prior to step a), digginga hole in the earth for the metallic structure, wherein the hole issized to leave a gap between the metallic structure and the earth, andlowering at least a bottom portion of the metallic structure into thehole. The section can be a section of the bottom portion.

In some examples, the cementitious product is a cementitious slurry. Themethod can further include combining a cementitious powder with water toform the cementitious slurry. The cementitious powder can be combinedwith the water in a ratio of less than or equal to 3 US gallons of waterper 55 lb of cementitious powder. The cementitious powder can becombined with the water in a ratio of between about 1.5 and about 3.0 USgallons of water per 55 lb of cementitious powder. The method canfurther include applying the cementitious slurry to the hole beforelowering at least the bottom portion of the metallic structure into thehole. Lowering the bottom portion of the metallic structure into thehole can force the slurry to fill the gap or the bottom portion of thepole.

In some examples, the cementitious product is a cementitious powder, andthe method further includes adding water to the cementitious powder.

In some examples, the method further includes, prior to step a),applying a jacket to the section. The jacket can be sized to leave a gaparound the section.

In some examples, the metallic structure is a pole or an anchor rod fora guy wire or a cladding on a non-metallic pole.

In some examples, the surround has a width of between about 0.5 inch andabout 10 inches.

In some examples, the method further includes applying a diverter arounda top edge of the surround, to direct water away from the metallicstructure.

In some examples, the cementitious matrix includes Portland cement. Insome examples, the particulate carbonaceous material includes calcinedpetroleum coke.

In some examples, the cementitious surround includes between 5 wt % and70 wt % Portland cement, and between 30 wt % and 90 wt % calcinedpetroleum coke. The cementitious surround can include up to 50% slag.

In some examples, the method further includes bracing the metallicstructure with at least one brace. The brace can be electricallyconductive and water impermeable. Bracing the metallic structure caninclude embedding the brace in the surround.

Methods for electrically grounding and corrosion-protecting a metallicstructure are disclosed. According to some aspects, a method forelectrically grounding and corrosion-protecting a metallic structureincludes: a) combining a cementitious powder with water to form acementitious slurry, wherein the cementitious powder comprises a cementand a particulate carbonaceous material, and wherein the cementitiouspowder is combined with the water in a ratio of less than or equal toabout 2.5 US gallons of water per 55 lb of cementitious powder; b)applying the cementitious slurry to at least a section of the metallicstructure; and c) curing the cementitious slurry to form a waterimpermeable and electrically conductive cementitious surround on thesection.

In some examples, the ratio is between about 2.5 US gallons of water and1.5 US gallons of water per 55 lb of cementitious powder. In someexamples, the ratio is about 2.5 US gallons of water per 55 lb ofcementitious powder. In some examples, the ratio is about 2.0 US gallonsof water per 55 lb of cementitious powder. In some examples, the ratiois about 1.8 US gallons of water per 55 lb of cementitious powder.

In some examples, the surround has a compressive strength of greaterthan or equal to about 50 psi. In some examples, the surround has acompressive strength of greater than or equal to about 2000 psi after 28days of curing.

In some examples, the method further includes, prior to step a): digginga hole in the earth for the metallic structure, wherein the hole issized to leave a gap between the metallic structure and the earth; andlowering at least a bottom portion of the metallic structure into thehole. The method may further include pouring the cementitious slurry into the gap, to apply the cementitious slurry to the bottom portion ofthe metallic structure.

In some examples, the cement includes Portland cement. In some examples,the particulate carbonaceous material includes calcined petroleum coke.In some examples, the cementitious powder includes between about 20 wt %and about 80 wt % Portland cement, and between about 30 wt % and about80 wt % calcined petroleum coke.

Intermediate assemblies, which are curable to yield an electricallygrounded and corrosion-protected assembly, are further disclosed.According to some aspects, an intermediate assembly that is curable toyield an electrically grounded and corrosion-protected assemblyincludes: a metallic structure, wherein at least a portion of themetallic structure is buried in the earth; and a cementitious slurryapplied to at least a section of the portion that is buried in theearth, wherein the cementitious slurry includes a cementitious productand water, wherein the cementitious product includes a cement and aparticulate carbonaceous material, and wherein the cementitious slurryincludes less than or equal to about 2.5 US gallons of water per 55 lbof cementitious product.

In some examples, the cementitious slurry includes between about 2.5 USgallons of water and 1.5 US gallons of water per 55 lb of cementitiousproduct. In some examples, the cementitious slurry includes about 2.5 USgallons of water per 55 lb of cementitious product. In some examples,the cementitious slurry includes about 2.0 US gallons of water per 55 lbof cementitious product.

In some examples, the metallic structure is a pole.

In some examples, the cement includes Portland cement. In some examples,the particulate carbonaceous material includes calcined petroleum coke.In some examples, the cementitious product includes between about 20 wt% and about 80 wt % Portland cement, and between about 30 wt % and about80 wt % calcined petroleum coke.

Cementitious slurries are further disclosed. According to some aspects,a cementitious slurry, which curable to form a water impermeable andelectrically conductive cementitious surround on a metallic structure,includes a cementitious product including between about 5 wt % and about70 wt % Portland cement, and between about 30 wt % and about 90 wt %calcined petroleum coke; and water; wherein the cementitious slurrycomprises less than or equal to about 2.5 US gallons of water per 55 lbof cementitious product.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings included herewith are for illustrating various examples ofarticles, methods, and apparatuses of the present specification and arenot intended to limit the scope of what is taught in any way. In thedrawings:

FIG. 1 is a partial and schematic cross-sectional view showing acementitious slurry being applied to a bottom portion of a utility pole;and

FIG. 2 is a partial and schematic cross-sectional view showing a utilitypole with a cementitious surround applied thereto;

FIG. 3 is a partial and schematic cross-sectional view showing an anchorrod with a cementitious surround applied thereto;

FIG. 4 is a perspective view of an example jacket usable with thecementitious surrounds described herein;

FIG. 5 is a partial and schematic cross-sectional view showing thejacket of FIG. 4 applied to the anchor rod and cementitious surround ofFIG. 3;

FIG. 6 is a perspective view of an example brace usable with thecementitious surrounds described herein;

FIG. 7 is a partial and schematic cross-sectional view showing the braceof FIG. 6 applied to the utility pole and cementitious surround of FIG.2; and

FIG. 8 shows the experimental setup of Example 2.

DETAILED DESCRIPTION

Various apparatuses or processes or compositions will be described belowto provide an example of an embodiment of the claimed subject matter. Noembodiment described below limits any claim and any claim may coverprocesses or apparatuses or compositions that differ from thosedescribed below. The claims are not limited to apparatuses or processesor compositions having all of the features of any one apparatus orprocess or composition described below or to features common to multipleor all of the apparatuses or processes or compositions described below.It is possible that an apparatus or process or composition describedbelow is not an embodiment of any exclusive right granted by issuance ofthis patent application. Any subject matter described below and forwhich an exclusive right is not granted by issuance of this patentapplication may be the subject matter of another protective instrument,for example, a continuing patent application, and the applicants,inventors or owners do not intend to abandon, disclaim or dedicate tothe public any such subject matter by its disclosure in this document.

Disclosed herein is a cementitious product that, when in its curedstate, forms a water impermeable and electrically conductive surroundfor buried portions (e.g. bottom portions) of metallic structures, orfor sections of such buried portions. Such structures can include thoseused in the electrical power distribution and transmission industry, orin the telecommunications industry, or in the street lighting industry,or in various other industries. For example, metallic structures caninclude poles (e.g. steel poles) such as utility poles ortelecommunications poles or street lighting poles. For further example,metallic structures can include anchor rods for guy wires. For furtherexample, metallic structures can include metallic parts of ancillarystructures (e.g. metal claddings on non-metallic structures such asconcrete poles or composite poles or wood poles). The cementitiousproduct can be used to facilitate installation of the metallic orancillary structure (i.e. can set and support a metallic utility pole ormetal-clad non-metallic utility pole, to hold the utility pole in agenerally vertical position), provide electrical grounding to themetallic or ancillary structure, and protect the buried portion of themetallic structure (or the section thereof) from corrosion.

The cementitious product can be applied to the metallic structure insitu. For example, the bottom portion of a metallic utility pole can beplaced in a hole that has been dug in the earth (e.g. into a hole dugfor the utility pole using an auger). The cementitious product, inslurry form or in powder form, can be poured around the bottom portionof the utility pole so that it is in direct contact with the utilitypole. The cementitious product can cure in-situ around the bottomportion of the utility pole (e.g. the slurry can cure in-situ, or thepowder can absorb environmental water (e.g. rain water) and then curein-situ), so that the cementitious product is between the utility poleand the earth and can form a barrier between the utility pole and theearth. When cured, the cementitious product can form a surround aroundthe bottom portion of the utility pole that (1) anchors the utility polein the earth (i.e. holds up or helps to hold up or supports or sets theutility pole in a generally vertical position, so that a separatebackfill material is not necessarily required); (2) is water impermeableto protect the bottom portion of the utility pole from corrosion; and(3) is electrically conductive to electrically ground the utility pole(e.g. to protect the utility pole from lightning strikes and powerlineground faults and prevent electrical fires).

As used herein, the term ‘cementitious product’ refers to a product thathas a cementitious matrix—i.e. a matrix that is a cement (e.g. Portlandcement), or consists essentially of a cement, or is made up largely of acement (i.e. at least 20% by weight of the matrix is a cement). Variouscomponents, as described below, can be dispersed in (or otherwise mixedwith) the cementitious matrix. The term ‘cementitious product’ can referto a dry product (also referred to herein as a ‘cementitious powder’), awet product (also referred to herein as a ‘cementitious slurry’), or asolid product (also referred to herein as a ‘cementitious surround’ orsimply as a ‘surround’).

As used herein, the term ‘electrically-conductive’ indicates that thecementitious surround has an electrical resistivity of less than orequal to 10,000 ohm·cm. For example, the cementitious surround may havean electrical resistivity of less than 500 ohm·cm, or between 2.0 ohm·cmand 5.0 ohm·cm.

As used herein, the term ‘water-impermeable’ indicates that the surroundhas a water permeability of less than or equal to 10⁻⁵ cm/s. Forexample, the surround may have a water permeability of 2.0×10⁻⁸ cm/s.

As used herein, the term ‘in situ’ indicates that cementitious productis applied to the metallic structure at the installation location of themetallic structure. For example, the statement that ‘the cementitiousproduct can be applied to the utility pole in situ’ indicates that thecementitious product can be applied to a bottom portion of the utilitypole after a hole has been dug and the bottom end of the utility polehas been positioned in the hole.

The cementitious products disclosed herein generally include aparticulate carbonaceous material (e.g. calcined petroleum coke)dispersed in the cementitious matrix (e.g. Portland cement). When cured,the cementitious matrix may provide the product with waterimpermeability, to protect the buried portion (or a section of theburied portion) of the metallic structure from corrosion, and theparticulate carbonaceous material may provide the product withelectrical conductivity, to electrically ground the metallic structure.For example, a cementitious powder can include a mixture of calcinedpetroleum coke, Portland cement, and optionally slag. In some examples,the cementitious powder can include a mixture of 50 wt % calcinedpetroleum coke and 50 wt % Portland cement. In other examples, thecementitious powder can include a mixture of between about 30 wt % and90 wt % calcined petroleum coke, between about 5 wt % and 70 wt %Portland cement, and between about 1 wt % and 50 wt % slag.

In order to form the cementitious surround, the cementitious powder canbe combined with water to form a slurry, which can then be applied indirect contact to the metallic structure in situ (e.g. poured into ahole that has been dug for a utility pole) and allowed to cure. In someexamples, the cementitious powder can be combined with water in a ratioof less than or equal to about 3 US gallons of water per 55 lb ofcementitious powder, for example between about 1.5 US gallons and 3.0 USgallons of water per 55 lb of cementitious powder. In one particularexample, the cementitious powder can be combined with water in a ratioof about 2.0 US gallons of water per 55 lb of cementitious powder. Thisratio may be particularly useful where the surround is formed on autility pole. In another example, the cementitious powder can becombined with water in a ratio of about 2.5 US gallons of water per 55lb of cementitious powder. This ratio may be particularly useful wherethe surround is formed on an anchor rod. Such cementitious slurries canbe generally thick and have low slump.

Alternatively, the initial step of combining with water can be omitted,and the cementitious powder can be applied in direct contact to themetallic structure in situ (e.g. poured into a hole that has been dugfor a utility pole). Water can then be added to the cementitious powderin-situ, or the cementitious powder can be left and allowed to absorbenvironmental water (e.g. rainwater). The cementitious product can thenbe allowed to cure.

The cementitious products disclosed herein can in some examples have agenerally low drying shrinkage, e.g. a drying shrinkage of less than orequal to about 0.20% after curing for 28 days, or a drying shrinkage ofless than about 0.015% after curing for 28 days.

After curing, the cementitious surround can be relatively strong — i.e.can have a compressive strength of greater than or equal to about 50 psi(i.e. greater than about 0.34 MPa). For example, the compressivestrength can be greater than 2000 psi (about 13.79 MPa), or about 4003psi (about 27.6 MPa) or about 4350 psi (about 30 MPa), or about 914 psi(about 6.30 MPa), or about 624 psi (about 4.30 MPa), or about 348 psi(about 2.40 MPa), or about 174 psi (about 1.20 MPa), or about 65 psi(about 0.45 MPa) after curing (e.g. after 28 days of curing).

Referring now to FIG. 1, an assembly is shown that includes a metallic(e.g. steel) utility pole 100 in situ. A portion (i.e. the bottomportion 102) of the utility pole has been lowered into a hole 104 thathas been dug in the earth 106 (e.g. dug into the earth 106 with an augeror a hydrovac or any other technique that involves removal of soil tocreate a hole). The hole 104 can be sized to have a diameter that isslightly larger than the utility pole 100, to leave a circumferentialgap 108 between the utility pole 100 and the earth 106. The gap 108 canhave a width W of, for example, between 0.5 inch and 10 inches, orbetween 1 inch and 6 inches. With the utility pole in this position, acementitious slurry 110 as described above can be applied to the bottomportion 102 of the utility pole 100, for example by pouring thecementitious slurry into the gap 108 (although FIG. 1 shows the slurry110 being poured from a pot, it may also be poured from a cement truckor other container). Alternatively, the cementitious slurry can first beapplied to the hole, and the bottom portion of the utility pole can thenbe lowered into the hole and pressed into the slurry. If the bottomportion of the utility pole is closed as shown, this can cause theslurry to rise and fill the gap, or, if the bottom portion of theutility pole is open (not shown), the slurry can fill the bottom portionas well as the gap. A concrete vibrator can optionally be used to removeair trapped in the slurry. The slurry can then be left to cure, forexample over a period of several days, to form the surround 112, asshown in FIG. 2. As mentioned above, the surround 112 is between thebottom portion 102 of the utility pole 100 and the earth 106 and canform a barrier between the bottom portion 102 of the utility pole 100and the earth 106, is electrically conductive to allow the utility pole100 to be electrically grounded, and is water impermeable to protect theutility pole 100 from corrosion.

As mentioned above, instead of applying a cementitious slurry to theutility pole 100, a cementitious powder can be applied to the utilitypole 100 (e.g. by applying the cementitious powder to the gap 108).Water can then be added to the cementitious powder in-situ, or thecementitious powder can be left and allowed to absorb environmentalwater (e.g. rainwater). The cementitious product can then be allowed tocure.

Referring to FIG. 2, in order to prevent water (e.g. rainwater) frompooling around the utility pole 100, which can lead to corrosion, adiverter 114 can be installed or applied around the utility pole 100, onthe top edge of the surround 112. The diverter 114 can be shaped todirect water away from the utility pole 100. The diverter 114 can beformed from a grout or polymeric material that is troweled around theutility pole 100. The diverter can optionally be or include anelectrically conductive material.

A grounding grid can optionally be installed around the utility pole,for safety.

Referring to FIG. 3, another example is shown, in which the assemblyincludes a metallic structure in the form of an anchor rod 300 for a guywire 316. The anchor rod 300 is shown in situ, with the anchor rod 300lowered into a hole that has been dug in the earth 306. In the exampleshown, the entire anchor rod 300 is buried. In the example shown, thehole is an auger hole dug into the earth 306 with an auger; inalternative examples, the hole can be a trench dug into the earth with abackhoe. The hole has a diameter that is slightly larger than the anchorrod 300, to leave a circumferential gap (not shown) between the anchorrod 300 and the earth 306. A cementitious slurry as described above hasbeen poured into the hole, to fill the gap between the anchor rod 300and the earth 306, and the slurry has cured to form the surround 312.Alternatively, a cementitious powder can be poured into the hole, tofill the gap between the anchor rod and the earth. Water can then beadded to the cementitious powder in-situ, or the cementitious powder canbe left and allowed to absorb environmental water (e.g. rainwater). Thecementitious product can then be allowed to cure.

In the example shown, an anchor 318 is mounted to the bottom portion 302of the anchor rod 300, to secure the anchor rod 300 in the earth. In theexample shown, the anchor 318 is fully embedded in the surround 312. Inalternative examples, the anchor can be either fully or partiallyoutside of the surround 312. The anchor can be of various configurations(e.g. a plate or a nut or another configuration).

In the example shown, the assembly of FIG. 3 further includes a diverter314, similar to the diverter 114 of FIG. 2.

Referring now to FIGS. 4 and 5 (where features that are like those ofFIG. 3 are referred to with the same reference numerals as in FIG. 3),in some examples, a jacket 420 can be used to encapsulate the surround312. The jacket 420 can be electrically conductive and waterimpermeable. For example, the jacket can include a polymeric matrix, anda particulate carbonaceous material dispersed in the polymeric matrix.Such materials are described in U.S. Pat. No. 10,333,234 B2 (Sirola etal.), which is incorporated herein by reference in its entirety. In theexample shown, the jacket 420 is in the form of a tube, which is formedin two pieces, 422 a, 422 b, which are positioned around the surround312.

The jacket 420 can be used in various scenarios, but may be particularlyuseful in repair or retro-fit scenarios. For example, in situationswhere an anchor rod 300 is already installed in the earth 306, it may berequired to dig up the earth 306 around the anchor rod 300 for variousreasons, leaving the anchor rod 300 exposed (i.e. leaving the entireanchor rod exposed, or leaving only a section of the anchor rod exposed)and in a relatively large hole (not shown) that may be too large to fillwith the cementitious product (i.e. having a diameter larger than theoriginal auger hole that was created for the anchor rod 300). In suchsituations, the jacket 420 can be positioned in the hole around anchorrod 300 (i.e. either around the entire anchor rod 300, or around onlythe exposed section of the anchor rod 300) and secured in place (e.g.using a fastener such as a zip tie). The jacket 420 can then be filledwith the cementitious material, e.g. by pouring a cementitious slurry asdescribed above into the jacket 420, to fill the jacket 420 (or bypouring a cementitious powder into the jacket 420). The slurry can thencure to form the surround 312, and the hole can be filled with earth306. In such examples, depending on how deep the hole around the anchorrod 312 has been dug, the surround 312 can be on the entire buriedportion of the anchor rod 312, or on only a section of the buriedportion of the anchor rod 312 (e.g. the top section).

Jackets as described above can also be used with structures other thananchor rods, e.g. poles.

Referring now to FIGS. 6 and 7 (where features that are like those ofFIGS. 1 and 2 are referred to with the same reference numerals as inFIGS. 1 and 2), in some examples, one or more braces 624 a-d (only oneof which is shown in FIG. 6) can be embedded in the surround 112 tofurther support the utility pole 100, particularly during the periodwhile the cementitious product is in the process of curing. The braces624 a-d can include a polymeric matrix, and a particulate carbonaceousmaterial dispersed in the polymeric matrix. Such materials are describedin U.S. Pat. No. 10,333,234 B2 (Sirola et al.), which is incorporatedherein by reference in its entirety. The braces 624 a-d can be in theform of elongate bars or rods or blocks (e.g. 4 inch×4 inch bars) thatare cut to length to fit the gap between the utility pole 100 and theearth 106. To install the braces 624 a-d, the bottom portion 102 of theutility pole 100 can be lowered into the hole 104 that has been dug inthe earth 106 (e.g. dug into the earth 106 with an auger). The braces624 a-624 d can then be positioned in the gap, around the utility pole100, so that they are generally wedged between the utility pole 100 andthe earth 106. The cementitious slurry as described above can then beapplied to the utility pole, enveloping the braces 624 a-624 d. Theslurry can then be left to cure, for example over a period of severaldays, to form the surround 112 with the braces 624 a-624 d embeddedtherein, as shown in FIG. 7.

In FIG. 7, four braces 624 a-624 d are shown (i.e. two lower braces 624a, 624 b, and two upper braces 624 c, 624 d). However, another number ofbraces can be used, such as four lower braces and four upper braces.

As mentioned above, the metallic structures described herein can includemetallic parts of ancillary structures (e.g. metal claddings onnon-metallic structures such as wood poles). In one particular example(not shown), the ancillary structure can be a wood pole (e.g. utilitypole), and the metallic structure can be a cladding on the bottomportion of the wood pole. The cladding can be, for example, a materialsuch as a foil. The foil can be, for example, a copper foil or steel(e.g. galvanized steel) foil that is wrapped around the bottom portionof the wood pole. A wire can connect the cladding to a power systemneutral of the utility pole. The bottom portion of the wood pole,together with the cladding, can be lowered into a hole that has been dugin the earth and a cementitious product (i.e. a slurry or a powder) canthen be applied to the cladding and allowed to cure to form a surround,as described above.

While the above description refers to portions of the metallicstructures (e.g. bottom portions) being buried in the earth and thesurround being on such buried portions, it is possible that the entiremetallic structure may be buried in the earth, and the surround may beon the entire metallic structure. For example, in the case of a metalliccladding on a wood pole, the entire cladding may be buried in the earthand the surround may surround the entire cladding. For further example,in the case of an anchor rod, the entire anchor rod may be buried in theearth and the surround may surround the entire anchor rod. Furthermore,the surround may in some examples be applied to only a section of theburied portion of the metallic structure. For example, in the case ofrepair to an anchor rod, the surround may be applied to only the sectionof the anchor rod that is exposed when a trench is dug (e.g. the top 3to 4 feet of the anchor rod).

While the above description provides examples of one or more processesor apparatuses or compositions, it will be appreciated that otherprocesses or apparatuses or compositions may be within the scope of theaccompanying claims.

To the extent any amendments, characterizations, or other assertionspreviously made (in this or in any related patent applications orpatents, including any parent, sibling, or child) with respect to anyart, prior or otherwise, could be construed as a disclaimer of anysubject matter supported by the present disclosure of this application,Applicant hereby rescinds and retracts such disclaimer. Applicant alsorespectfully submits that any prior art previously considered in anyrelated patent applications or patents, including any parent, sibling,or child, may need to be re-visited.

EXAMPLES Example 1—Material Properties of Cementitious Products

Various cementitious powders were made, as shown in Tables 1 to 3. Thepowders were prepared by blending the components in a pneumatic blender.The powders were stored in 55 lb bags.

TABLE 1 Composition of Cementitious Powder 1 Component Weight %Particulate carbonaceous material: 50.0 CC60 Calcined Petroleum Coke(Oxbow Calcining LLC) Portland Cement 50.0 (Contempra Type GUL PortlandLimestone Cement, St Mary’s Cement)

TABLE 2 Composition of Cementitious Powder 2 Component Weight %Particulate carbonaceous material: 70.0 CC60 Calcined Petroleum Coke(Oxbow Calcining LLC) Portland Cement 30.0 (Contempra Type GUL PortlandLimestone Cement, St Mary’s Cement)

TABLE 3 Composition of Cementitious Powder 3 Component Weight %Particulate carbonaceous material: 80.0 CC60 Calcined Petroleum Coke(Oxbow Calcining LLC) Portland Cement 20.0 (Contempra Type GUL PortlandLimestone Cement, St Mary’s Cement)

The cementitious powders were tested for electrical resistivityfollowing a modified ASTM G187-05 procedure: Standard Test Method forMeasurement of Soil Resistivity using the Two Electrode Soil Box Method.Cementitious powder (10 g) was placed in a fixture in between 2 brassplatens. An Instron was used to apply a force of 192 lbs/int to thefixture, and the resistivity of the sample (measured between the 2 brassplatens) was measured using a rectifier. Results are shown in Tables 4to 6.

The cementitious powders were then mixed with water (at various ratiosset out below) to yield a cementitious slurry. Mixing was conductedusing a drill with a grout mixing paddle until the slurry reached asmooth consistency. The slurry was then cured (as described below), andthe cured product was tested for material properties, including waterpermeability, shrinkage, and compressive strength.

For water permeability tests, 551 b of cementitious powder was combinedwith 3 US gallons of water. The cementitious slurry was then poured into4 inch×8 inch PVC cylinders in 2 even layers. Each layer was rodded toremove entrained air. Lids were sealed on the cylinders and the materialwas allowed to cure for 28 days in the cylinder (ambient temperature andhumidity conditions) before being demoulded and tested for waterpermeability. Water permeability tests followed ASTM D5084: HydraulicConductivity of Saturated Porous Materials using a Flexible WallPermeameter—Constant Volume. The demoulded samples were placed into thepermeameter and subjected to an effective stress of 2.6 psi, and thepermeability rate of water through the material was calculated. Resultsare shown in Tables 4 to 6.

For shrinkage tests, 551 b of cementitious powder was combined with 3 USgallons of water. Shrinkage tests followed ASTM C157: Length Change ofHardened Hydraulic-Cement Mortar and Concrete. The cementitious slurrywas cast into prisms for linear shrinkage testing. Prism specimens werewet cured in lime saturated water for 28 days, followed by 28 days ofair storage in a humidity and temperature controlled drying room.Shrinkage was measured after demoulding, after 28 days of wet curing,and after 4, 7, 14 and 28 days of air storage. Results (shown in Tables4 to 6) show the shrinkage after 28 days of air storage.

For compressive strength tests, up to three water ratios were tested: 55lb of cementitious powder combined with 1.8 US gallons of water, 55 lbof cementitious powder combined with 2.5 US gallons of water, and 55 lbof cementitious powder combined with 3.0 US gallons of water. Eachcementitious slurry was poured into 4 inch×8 inch PVC cylinders in 2even layers. Each layer was rodded to remove entrained air. Lids weresealed on the cylinders and the material was allowed to cure for 28 daysin the cylinder (ambient temperature and humidity conditions) beforebeing demoulded and tested for compressive strength. Compressivestrength tests followed CAN/CSA A.23.2-14. After demoulding the sampleswere placed in between 2 plates. Force was applied until the materialfractured. The amount of force required to fracture the material is therecorded compressive strength. Results are shown in Tables 4 to 6.

TABLE 4 Properties of Cured Surround Material 1 Property Value (average)Permeability to Water (n = 2) 2.0 × 10⁻⁸ cm/sec Shrinkage (n = 3) 0.015%Electrical Resistivity (n = 5) 2.8-5.0 Ω · cm Compressive Strength 1.8US gallons of water/bag (n = 2) 7005 psi (48.3 MPa) 2.5 US gallons ofwater/bag (n = 2) 4569 psi (34.5 MPa) 3.0 US gallons of water/bag (n =2) 4003 psi (27.6 MPa)

TABLE 5 Properties of Cured Surround Material 2 Property Value (average)Permeability to Water (n = 4) 1.85 × 10⁻⁷ cm/sec Electrical Resistivity(n = 8) 0.5-2.0 Ω · cm Compressive Strength 3.0 US gallons of water/bag(n = 2) 914 psi (6.30 MPa)

TABLE 6 Properties of Cured Surround Material 3 Property Value (average)Permeability to Water (n = 4) 1.46 × 10⁻⁶ cm/sec Electrical Resistivity(n = 6) 0.4-3.0 Ω · cm Compressive Strength 3.0 US gallons of water/bag(n = 2) 348 psi (2.40 MPa)

Example 2—Corrosion Protection of Metallic Structures by CementitiousSurrounds

Cementitious products were tested for their ability to protect copper,steel, and galvanized steel structures from corrosion.

Copper:

Copper samples (34 inch×3 inch rectangular strips having a thickness of0.2 mm (0.008 inch)) were connected to insulated wire, which was thenconnected to a rectifier. One strip was left bare and the second stripwas encased in a 4 inch×8 inch cementitious surround.

The cementitious surround was made using a cementitious powder of thecomposition shown in Table 1. A cementitious slurry was made by adding55 lbs of the cementitious powder to 3.3 US gallons of water and mixing,as described above. The copper samples were embedded in the slurry in a4 inch×8 inch PVC cylinder as described above, and the slurry wasallowed to cure for 13 days (ambient temperature and humidityconditions) before demoulding.

Both samples (i.e. bare strip and encased strip) were buried in topsoil.Sodium sulfate (20 g) was added to the soil and water was regularlyadded to ensure the soil was wet and salty (to simulate worst caseconditions). Samples were connected to the rectifier in series, and 3 mAwas applied to each sample for 60 days. The experimental setup is shownin FIG. 8. In FIG. 8, the following reference numerals are used:800—regulated power supply; 802—insulated positive wire; 804—testcontainer; 806—steel rebar (cathodic); 808—bare metal (anodic);810—insulated bond wire; 812—metal encased in cementitious surround(anodic); 814—steel rebar (cathodic); 816—test container; 818—insulatednegative wire; 820—soil.

The samples were then removed from the soil. The encased strip wasremoved from the cementitious surround. Both copper strips were thenweighed. Results are shown in Table 7.

Steel:

Steel samples (1.75 inch×¾ inch rectangular sections having a thicknessof 1/4 inch) were connected to insulated wire, which was then connectedto a rectifier. One section was left bare and the second section wasencased in a 4 inch×8 inch cementitious surround. The cementitioussurround was made as described above for copper; however the slurry wascured for 28 days.

Both samples (i.e. bare section and encased section) were buried intopsoil. Sodium sulfate (20 g) was added to the soil and water wasregularly added to ensure the soil was wet and salty. Samples wereconnected to the rectifier in series, and 3 mA was applied to eachsample for 30 days. The experimental setup was the same as shown in FIG.8.

The samples were then removed from the soil. The encased section wasremoved from the cementitious surround. Both steel sections were thenweighed. Results are shown in Table 7.

Galvanized Steel:

Galvanized steel samples were 1.75 inch×¾ inch rectangular sectionshaving a thickness of ¼ inch. Galvanizing met ASTM A123/A123M, and thesamples had a zinc coating of at least 0.025 mm (0.001 inch). Thesections were connected to insulated wire, which was then connected tothe rectifier. One section was left bare and the second section wasencased in a 4 inch×8 inch cementitious surround. The cementitioussurround was made as described above for steel. The experiment wasconducted as described above for steel. Results are shown in Table 7.

The results indicate that the cementitious products disclosed herein caninhibit or prevent corrosion of metal including copper, steel, andgalvanized steel.

TABLE 7 Electrical Corrosion Resistance of Various Metals Percentage ofSample Consumed after 30 days or 60 days Sample (%) Copper withoutCementitious Surround 94.80 (in direct contact with soil) Copper Encasedin Cementitious Surround 0.00 Steel without Cementitious Surround 5.79(in direct contact with soil) Steel Encased in Cementitious Surround0.00 Galvanized Steel without Cementitious Surround 7.70 (in directcontact with soil) Galvanized steel Encased in Cementitious 0.00Surround

We claim:
 1. A method for electrically grounding andcorrosion-protecting a metallic structure, comprising: a) combining acementitious powder with water to form a cementitious slurry, whereinthe cementitious powder comprises a cement and a particulatecarbonaceous material, and wherein the cementitious powder is combinedwith the water in a ratio of less than or equal to about 2.5 US gallonsof water per 55 lb of cementitious powder; b) applying the cementitiousslurry to at least a section of the metallic structure; and c) curingthe cementitious slurry to form a water impermeable and electricallyconductive cementitious surround on the section.
 2. The method of claim1, wherein the ratio is between about 2.5 US gallons of water and 1.5 USgallons of water per 55 lb of cementitious powder.
 3. The method ofclaim 1, wherein the ratio is about 2.5 US gallons of water per 55 lb ofcementitious powder.
 4. The assembly of claim 1, wherein the ratio isabout 2.0 US gallons of water per 55 lb of cementitious powder.
 5. Theassembly of claim 1, wherein the ratio is about 1.8 US gallons of waterper 55 lb of cementitious powder.
 6. The method of claim 1, wherein thesurround has a compressive strength of greater than or equal to about 50psi.
 7. The method of claim 1, wherein the surround has a compressivestrength of greater than or equal to about 2000 psi after 28 days ofcuring.
 8. The method of claim 1, further comprising, prior to step a):digging a hole in the earth for the metallic structure, wherein the holeis sized to leave a gap between the metallic structure and the earth;and lowering at least a bottom portion of the metallic structure intothe hole.
 9. The method of claim 8, further comprising pouring thecementitious slurry in to the gap, to apply the cementitious slurry tothe bottom portion of the metallic structure.
 10. The method of claim 1,wherein the cement comprises Portland cement.
 11. The method of claim 1,wherein the particulate carbonaceous material comprises calcinedpetroleum coke.
 12. The method of claim 1, wherein the cementitiouspowder comprises between about 20 wt % and about 80 wt % Portlandcement, and between about 30 wt % and about 80 wt % calcined petroleumcoke.
 13. An intermediate assembly that is curable to yield anelectrically grounded and corrosion-protected assembly, comprising: ametallic structure, wherein at least a portion of the metallic structureis buried in the earth; and a cementitious slurry applied to at least asection of the portion that is buried in the earth, wherein thecementitious slurry comprises a cementitious product and water, whereinthe cementitious product comprises a cement and a particulatecarbonaceous material, and wherein the cementitious slurry comprisesless than or equal to about 2.5 US gallons of water per 55 lb ofcementitious product.
 14. The intermediate assembly of claim 13, whereinthe cementitious slurry comprises between about 2.5 US gallons of waterand 1.5 US gallons of water per 55 lb of cementitious product.
 15. Theintermediate assembly of claim 13, wherein the cementitious slurrycomprises about 2.5 US gallons of water per 55 lb of cementitiousproduct.
 16. The intermediate assembly of claim 13, wherein thecementitious slurry comprises about 2.0 US gallons of water per 55 lb ofcementitious product.
 17. The intermediate assembly of claim 13, whereinthe metallic structure is a pole.
 18. The intermediate assembly of claim13, wherein the cement comprises Portland cement.
 19. The intermediateassembly of claim 13, wherein the particulate carbonaceous materialcomprises calcined petroleum coke.
 20. The intermediate assembly ofclaim 13, wherein the cementitious product comprises between about 20 wt% and about 80 wt % Portland cement, and between about 30 wt % and about80 wt % calcined petroleum coke.
 21. A cementitious slurry curable toform a water impermeable and electrically conductive cementitioussurround on a metallic structure, the cementitious slurry comprising: acementitious product comprising between about 5 wt % and about 70 wt %Portland cement, and between about 30 wt % and about 90 wt % calcinedpetroleum coke; and water; wherein the cementitious slurry comprisesless than or equal to about 2.5 US gallons of water per 55 lb ofcementitious product.